Stock DV Broken?

[Saedster]

Good morning people!

So basically I have started to notice a sound coming from my stock DV when I'm driving. Usually i drive with music on but one odd time where I wasn't I heard a sort of chatter from it, which at first i didn't recognize as a sound from my DV as I always thought they make more of a whistling sound. basically the sound is not there when I'm not driving and it only comes up when I push the car slightly. I tried to capture the sound but I couldn't make it happen due to the wind noise covering it up. it sounds something like this : just not as loud and prominent.

So what is the recommended course of action here? how do i diagnose it and make sure that it actually is broken, if it is, can I still drive with it or will this result in pressure loss from my turbo?

 

[aragorn]

A new ones about 30quid, just change it.

And yes, mine sounded like your video when it was bust, though as you say, not as prominent, you needed to get a bit of load on it rather than just revving it at idle.

 

[Alex C]

http://www.audi-sport.net/xf/thread...then-holds-vacuum-faulty.255066/#post-2584103

 

[Saedster]

I'm thinking of replacing the dv anyways now as i've also ordered an induction kit and planning to map. Any reccomendation on what valve to get? Forge is kinda out of my price range at 120+ quidd , i was looking for something between 30-80?
I've seen 'Driftwerks' valves on ebay does anyone have something to say about those valves? They have different ones between 20-60 quidd , thanks!

 

[Tj 0785]

Just get a new one from Audi no point in paying more when the original is probably best

 

[ayfreetee]

Bill recommends the standard Bosch item I believe.

 

[Stuart B]

there are some discussions as to whether the older 710N has a stronger spring for the High PSI Mapped Turbo over the 710P which is fine for a S4 Bi Turbo at a lower pressure

 

[<tuffty/>]

Just fit a brand new genuine one thats designed for the car... they work and are relatively cheap... you don't need anything special at this power level and std OE ones have been tested to hold 30psi with no leaks...

Don't fall foul of internet myth....

<tuffty/>

 

[badger5]

I'm thinking of replacing the dv anyways now as i've also ordered an induction kit and planning to map. Any reccomendation on what valve to get? Forge is kinda out of my price range at 120+ quidd , i was looking for something between 30-80?
I've seen 'Driftwerks' valves on ebay does anyone have something to say about those valves? They have different ones between 20-60 quidd , thanks!

Std Oe one works fine.

 

[Alex C]

there are some discussions as to whether the older 710N has a stronger spring for the High PSI Mapped Turbo over the 710P which is fine for a S4 Bi Turbo at a lower pressure

the diverter valve uses boost pressure + spring force to close the valve so it doesn't matter what boost your running - the more boost the higher the clamping force

 

[Erikn89nl]

the diverter valve uses boost pressure + spring force to close the valve so it doesn't matter what boost your running - the more boost the higher the clamping force

Not entirely true, as boost pressure will also be exerting force in the 'exit' direction... but as @<tuffty/> said, up to 30psi it's no problem

 

[<tuffty/>]

Pressure equalises both sides, spring is more a return spring than anything else...

Only reason stiffer springs have been suggested in the past is to mask the effect of leaky aftermarket valves...

Early OE DV's were a little prone to the diaphragm splitting but consider how long its been on there and the environment it lives in... it doesn't do that bad a job surviving all things considered...

<tuffty/>

 

[Alex C]

Not entirely true, as boost pressure will also be exerting force in the 'exit' direction... but as @<tuffty/> said, up to 30psi it's no problem

my understanding is that the top side of the diaphragm is exposed to the force exerted by both the spring and the boost pressure from the inlet manifold, the underside of the diaphragm is exposed to the pressure in the TIP (0psi boost)

The side entry is at full boost pressure from the charge pipe but when the valve is closed the underside area of the diaphragm is not exposed to it and therefore that pressure is isolated having no net effect to the force balance across the valve

if i want to lift something up i lift it up; i don't push it in the side

unless the DV has been fitted the wrong way round of course...

 

[Erikn89nl]

Fair enough, didn't mean to start an argument about it

 

[Alex C]

Fair enough, didn't mean to start an argument about it

no worries; i didn't take it that way

 

[SoljahofSensi]

Mine has started doing this evening, I've got a forge 007 but managed to look under the bonnet while it was still light and noticed the rubber vac hose going into the top was cracked so probably why it's not working properly.

 

[badger5]

unless the DV has been fitted the wrong way round of course...

which is fashionable in some circles - lol